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Sometimes we might see areas where convection scheme is active and HCCT is diagnosed whilst the resulting cloud cover is very little (less than 1%) and the cloud scheme is not able to produce clouds as shown in Fig. 3. This can happen in areas of very dry air where the cloud scheme evaporates all the water from the ongoing convection or the source of water is so small that the resulting cloud cover is less than 1%.
Fig. 3. HCCT, HCCT-CBH and Cloud cover for an area over Antarctica where convection is active and HCCT is diagnosed but the resulting cloud cover is very small, in some locations less than 1%.